Head & Neck Embryology

Front 1

Nerve of 1st pharyngeal arch

Back 1

CN V

Front 2

Nerve of 2nd pharyngeal arch

Back 2

CN VII

Front 3

Nerve of 3rd pharyngeal arch

Back 3

CN IX

Front 4

Nerve of 4th-6th pharyngeal arch

Back 4

CN X

Front 5

Cartilage derivatives of 1st arch

Back 5

incus, malleus
greater wing of sphenoid
roots of pterygoid plates
sphenomandibular ligament
mandible

Front 6

Muscle derivatives of 1st arch

Back 6

muscles of mastication
mylohyoid
ant. belly of digastric
tensor veli palatini
tensor tympani

Front 7

Cartilage derivatives of 2nd arch

Back 7

stapes
styloid process
stylohyoid ligament
lesser horn and upper body of hyoid bone

Front 8

Muscle derivatives of 2nd arch

Back 8

muscles of facial expression
posterior belly of digastric
stylohyoid
stapedius

Front 9

Cartilage derivatives of 3rd arch

Back 9

greater horn and lower body of hyoid bone

Front 10

Muscle derivative of 3rd arch

Back 10

stylopharyngeus

Front 11

Cartilage derivatives of 4-6th arch

Back 11

thyroid cartilage
cricoid cartilage
arytenoid cartilage

Front 12

Muscle derivatives of 4-6th arch

Back 12

cricothyroid
constrictors of pharynx
intrinsic muscles of larynx
striated muscles of esophagus

Front 13

What are special sense placodes derived from?

Back 13

ectoderm

Front 14

What does head mesenchyme condense to form?

Back 14

non-retinal parts of eyeball, skin of face, bones of neurocranium, dura mater

Front 15

What innervates the structures that derive from head mesenchyme (NCC)?

Back 15

CN V

Front 16

What do somitomeres and somites arise from?

Back 16

paraxial mesoderm

Front 17

Nerve and structure associated with somite 1

Back 17

CN X
Laryngeal muscles
pharyngeal constrictors

Front 18

Nerve and structures associated with somites 2-4

Back 18

CN XII
Tongue muscles

Front 19

pharyngeal cleft

Back 19

ectoderm that separates arches externally

Front 20

pharyngeal pouch

Back 20

endoderm that separates arches internally

Front 21

pharyngeal membrane

Back 21

forms between clefts and pouches--ectoderm and endoderm

Front 22

Contents of pharyngeal arches

Back 22

bar of cartilage
muscle component
nerve
aortic arch artery

Front 23

Pretrematic nerves

Back 23

Opthalmic division of trigeminal
Chorda tympani (CN VII)
Tympanic branch of CN IX
Superior laryngeal branch of CN X

Front 24

What does 1st cleft and membrane become in the adult?

Back 24

external acoustic meatus and tympanic membrane

Front 25

Adult derivatives of 1st pharyngeal pouch

Back 25

tubotympanic recess
middle ear cavity
mastoid antrum
eustachian tube

Front 26

Adult derivatives of 2nd pharyngeal pouch

Back 26

tonsillar fossa
palatine tonsils

Front 27

Adult derivatives of 3rd pharyngeal pouch

Back 27

thymus
inferior parathyroid glands

Front 28

Adult derivative of 4th pharyngeal pouch

Back 28

superior parathyroid glands

Front 29

Adult derivative of 5th pharyngeal pouch

Back 29

ultimobranchial body

Front 30

tongue primordia of 1st arch

Back 30

tuberculum impar and lateral lingual swelling

Front 31

tongue primordia of 3rd and 4th arch

Back 31

hypobranchial eminence

Front 32

What do the occipital somites become?

Back 32

Intrinsic tongue muscles
Extrinsic tongue muscles except palatoglossus

Front 33

Adult derivative of frontonasal prominence

Back 33

forehead, nose, philtrum, primary palate

Front 34

Adult derivatives of maxillary prominence

Back 34

upper cheek, maxilla, zygoma, lateral portion of upper lip, secondary palate

Front 35

Adult derivatives of mandibular prominence

Back 35

lower lip, lower cheek, mandible